I just rewrote the system of equations so that the variables we want to solve for are lined vertically lined up.
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OmnomnomnomAug 21 '13 at 13:45

The phrase, "multiplication-addition", means nothing to me, and I've been teaching Linear Algebra for 35 years.
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Gerry MyersonAug 21 '13 at 13:46

@GerryMyerson after googling, I realize that not everyone uses the same term for it. That's the term I heard for Gaussian elimination before I was told it was Gaussian elimination.
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OmnomnomnomAug 21 '13 at 13:48